Sonic signalling and ranging apparatus for marine use



May 3, 1960 M. L. Mac ADAM EI'AL 2,935,565

SONIC SIGNALLING AND RANGING APPARATUS FOR MARINE USE 2 Sheets-Shut A Filed Feb. 26. 1'954 I I POWER SUPPLY AMPLIFIER M L. MAc ADAM, cleceasecl, .3 Dorofhy MCA O'AM execu'relxj WALTER LEMMo/v STEPHEN 5. Srem No w/cz,

INVENTORS BY Q WMQ ATTORNEY 2,935,565 some SIGNALLING AND RANGING APPARATUS FOR MARINE USE Filed Feb. 26, 1954 y 3, 1960 M. L. Ma ADAM ETAL 2 Sheets-Sheet 2 INVENTORS MARK L-MAcAd deaewse ATTORNEY power, far beyond the range of a human voice.

SONIC SIGNALLING AND RANGING APPARATUS FOR MARINE USE 'Mark L. MacAdam, deceased, late of Brockton, Mass.,,hy

Dorothy C. MacAdam, executrix, Brockton, Mass, Walters. Lemmomgkiverside, Conn, and Stephen S. Stefanowicz, South Weymouth, Mass, assignors to Radio Industries Corporation, New York, N.Y., a corporation of New York Y ApplicationFebruary 26, 1954, Serial No. 412,908

" w 2 Claims. c1. 1-794 his invention p s to signalling systems and ap- 'paratus, and has for its principal object the provision of an integrated sonic signalling system for use by marine craft as an aid to operation and navigation.

' It is a more specific object of the inventionto provide a combination of electrical apparatus having a multiplicity of different functions, all useful in the operation of marine or water-borne craft. Thus/the invention provides for electronic amplification of speech from the cabin, bridge or other control point of a craft, the amplified speech 7 being projected from the craft by a suitable loudspeaker.

This feature permits the operator todirect instructions, inquiries, warnings or the like to relatively remote points, without leaving his usual control position or station. Other boats, docks, bridge tenders and the like may be hailed easily and directly by the pilot or operator in his cabin.

, qThe invention also provides for the reception and ampli fication of sounds external to the craft, so that answering hails, advice orvthe' like may be heard readily by the operator at his station. The invention utilizes for this purpose the same transducer (loudspeaker) as a microphone, and since the latter is mounted outside the cabin or enclosure, it is able to pick up sounds from afar much more clearlythan can the operator himself. The electronic amplification provided permits a further increase in'range.

for the production of such signals are readily and efficiently obtained by a switch-controlled modification inan amplifying channel, so that a minimum amount of additional equipment is required.

Still another important object of the invention is to provide a signal system of the above type which can be used as a sound-ranging signal, in connection with the 'signal receiving and amplifyingsystem already referred to above. To this end, the apparatus is arranged so that immediately upon the production of a short blast of sound of a predetermined frequency, the receiving equipment is put in condition to receive the echo produced when the signal is reflected from another object (boat,

pier, coastal building or the like), and means are provided for measuring the echo time to arrive at a figure indicative of the distance of such object, In connection with a loud-pseaker (which operates also as a microphone) mounted for-adjustment in azimuth, the apparatus pro vides for accurate information as to the position of the 70 vessel relative to nearby visible or invisible objects, e.g., at

night or in fog conditions.

-' ease, safety .and enjoyment of the use of" such craft,

The invention accomplishes the above obiec'tsiby a compact and efiicient combination of apparatusarranged to accomplish the desired functions with aminimum amount of equipment, for low cost, compactness of installation and low power drain. It has been found to be highly practical for small and medium sized-vesselsnot ordinarily equipped with electronic signalling and-navigational aids, and contributes in an important way to the whether by commercial operators or sportsmen. I

The equipment may be powered from an. ordinary alternating current power supply, if. available on the'vessel, I

but its power requirements are so light that itcan equally well be energized froma six-volt storage battery or the like, with a suitable vibratory or motor-generator type of inverter. vacuum tubes employed, it is practical .to designthe ap' paratus so that the standby power is very low, yet'thegsys tem is ready for immediate use when required.

The invention will now be described in, connection with a specific and preferred embodiment thereof, it being understood that various modifications in the details thereof may be made Without departing from the spirit or scope of the invention. Reference is now made tothe accompanying drawings, showing such a preferred embodiment, and in which Fig. 1 is a view in elevation showing general installaf tion of the novel system upon a marine vessel of moderate size,

Fig. 2 is a, "view partially in block diagram form, 'show ing the major electrical components of the equipment and their. interconnections, and

Fig. 3 is a schematic wiring diagram showing the ooh}. I nections and controls for theflcomplete system.

A thorough understanding of the invention will be aide by a brief recapitulation of the principal functions of the system: V

(1) To enable theuser to project his voice, ampL'fiedQ:

many times, to a remote place, and to enable him to listen to sounds outside the vessel, eitherin the form of speech, signals or range echoes.

(2) To enable the operator to produce and control 'an audible signal or tone, of large or selected amplitude, as

a signal, warning or echo source. I

(3) To enable the operator to establish the prcscnce'of nearby objects, .even though invisible, bythe echo resulting from a signal generated as in (2) above, and to esti mate its distance by timing the echo delay.

(4) If desired, to enable the operator to estimate the f direction of objects by controlling the orientation of his sound emitter; and noting the effect on the amplitude of, 7

received sounds, such as echoes, or by listening toe-xternally produced sounds such as from buoy'sorthe like.

Referring now to Fig. 1 of the drawings, there is; illustrated a marine craft or vessel 10 having a cabinor en?" closure 12 in the forward or other portion of which an operator is stationed. At this position, he will normally be in position to; control the engine and steeringapparatus. At any desired external position, here shown as a forward position on the hull, there, is mounted a coma.

bined loud-speaker and microphone or a sound pick-up 14, which may be a moving-coil dynamic speaker of known form. As shown, the speaker 14 is mounted for rotation in azimuth, as upon a post 16, and'a pulley 18 is provided connected by a cable 20 toaiwheel 2 2 within the cabin, so that the direction of maximum emission or sensitivity of the speaker may be adjusted at will- The I wheel 22 is provided with proper indicia so that; the-direc f tion of the speaker 14 relative to the longitudinahaxis of the boat may be determined. Withinthe Cabr ra,-

and adjacent the operators normal positiomis placedthe remainder of the apparatus constituting the invention,

i atented May 7 By the use of quick-heating filaments for'the here shown as a control box 24, an amplifier 2'6 and a power supply unit 28. Preferably these components are mounted adjacent one another upon a bulkhead or other support, but obviously the amplifier and power unit may be otherwise disposed if conditions necessitate.

As shown in Fig. 2, the amplifier unit is connected to the speaker 14 and to the power supply unit 28 shown as receiving electric energy from a battery 30. The amplifier unit is also connected to the control box 24 by a suitable cabling. The latter box carries a hand telephone 32 having the usual transmitter 34, preferably of the close-talking type (to avoid interference from engine noise and the like), a receiver 36, and a push-button switch 38 of the push-to-talk type. An on-off switch 40 enables the unit to be disconnected from the power source. On the front panel of control box 24- there is a function selector switch 42 to be described in detail below, and a pilot lamp 44 indicating when the equipment is turned on. A jack 46 permits a separate head telephone to be employed for listening purpose, where the operator wishes to have both hands free. A knob 48 operates a volume control potentiometer, to be described below.

The remaining item shown on control box 24 is a flasher lamp 50, used for timing the echoes received during distance ranging operations, in a manner to be described. Preferably, for convenience in installation and maintenance, the various major units of the equipment are connected by cables terminating in suitable plugs fitting corresponding sockets in the other units.

The manner in which the various functions and operations are carried out will best be understood by referring now to Fig. 3, in which all essential parts are shown with their interconnections in detail. As there shown, separate amplifiers are used for listening and for talking, and the latter is also employed as the oscillator for generating the signal tones. The pushbutton switch 38 of the handset is used not only to convert from talk condition to listen" condition, when the selector switch 42 is in the talk-listen position, but it also controls the emission of the signal and ranging tones when the switch 42 is in signal and range positions. Switch 42 is shown in Fig. 3 as a five-position four-deck control, one position being provided for turning all power off. If a master switch such as 40 is provided (shown in both Figs. 2 and 3), this last position, to which the switch 42 is shown turned in Fig. 3, may be omitted.

Power circuits A source of alternating current power is indicated in Fig. 3 by numeral 52, it being understood that this may be from any available source or may be derived from converter components in the power supply casing 28 of Fig. 2. The supply circuit passes through the primary winding of a power transformer 54 and thence to the first deck (A) of switch 42, where it is extended over the bridged contacts 56 through fuse 58 (and on-off switch 40) back to the supply line. This permits the on-oif function to be performed either by the switch 40 or by the selector switch 42, as desired.

One secondary winding 60 of transformer 54 has one side grounded as at lead 62 and the other side connected to a conductor designated Z which terminates at the wiper of the second switch deck (B). The last three contacts of this deck are bridged and connected to a conductor Y which leads to the cathode heaters of amplifier tubes 64, 66, 68, 70 and 72, tubes 68 and 79 being shown as the two halves of a twin triode type. At level B of switch 42, therefore, provision is made for disabling the amplifier comprising those tubes, when the switch 42 is in the talk position; such amplifier is used only for listening purposes.

Another secondary winding 74 of transformer 54 has its high voltage terminals connected to the anodes of a full-wave rectifier tube 76, and its center-tap grounded at lead 62, to provide a usual form of high voltage supply for the anodes of all of the vacuum tubes. The filament of rectifier 76 is energized by a third (low voltage) secondary winding 78, and is connected as at lead 80 to provide the positive output voltage.

The anode supply voltage is smoothed in the usual way as by filter 82 and applied to a potentiometer 84 which supplies the desired anode voltage to lead 86.

A control relay $8 is used to convert the circuitry from using the element 14 as a loud-speaker to operation thereof as a microphone or sound pick-up, and for other purposes. Its functions will be described in more detail below, but for the present it will be noted that its coil has one side connected to a lead Z connected to one side of secondary winding 6G. When push-to-talk (handset) button 38 is closed, a circuit is completed from secondary winding 60, the relay coil, the button 33 and ground to operate the relay contacts. When so operated, contact set a of the relay connects the anode supply from filter 82 over lead 89 to the anode circuits of the vacuum tubes 90, 92 and 94 of a combined amplifier-oscillator. The cathode heaters of these tubes are also energized by connection to the lead Z.

Listen amplifier The Listen amplifier, including tubes 64, 66, 68, 70 and 72 is used for amplifying sounds picked up by the speaker 14 and repeating them to the operator at the receiver 36 of the handset. It is to be energized whenever the selector switch is in any of its last three positions, and hence the filament secondary through lead Z is connected (as mentioned above), in the last three positions of deck B of switch 42, to a common heater circuit lead Y leading to the heaters of these tubes. The signal input circuit for this amplifier may be traced from speaker 14 (now acting as a microphone) through the normally closed contact sets c and d of relay 88 to leads 96 and thence to input transformer 98. Tubes 64 and 66 form a conventional cascaded voltage amplifier, the output of tube 66 being coupled to the grid-cathode circuit of the first triode 68 (shown as half of a twin triode) employed as an isolating cathode-follower stage feeding, by the common cathode resistor 106, the grid-cathode circuit of triode 70. A filter network 102 gives the amplifier an emphasized characteristic in the voice frequency range, and the signal therefrom is conveyed to the output amplifier tube 72 feeding output transformer 104. One side of the secondary winding of the output transformer is conencted to ground, the other side via lead 106 to the receiver 36 of the handset. In order to permit an auxiliary headset to be used (so that the operators hands will be free during long listening period) a lead 108 connects the output of tube 72 also to the jack 46 into which either such a headset or even a small loudspeaker may be plugged. When employed, the output to this speaker will be cut off by a short circuit to ground over contacts b of relay 88 whenever the push-to-talk button is operated. This prevents the acoustic output of the local speaker from feeding into the handset transmitter 34 at such times.

Talk amplifier With the selector switch 42 in its second (talk) position or third (talk-listen) position, the talk amplifier will be energized. For clarity, the switch positions are referred to herein considering the position shown in Fig. 3 (off condition) as the first position, the others following in numerical order as the wipers are turned counter-clockwise. In the second position, deck A energizes the power transformer, deck B deenergizes the heaters of the listen amplifier, deck C interrupts a circuit which later supplies voltage to the flasher circuit (to be described), and deck D connects the transmitter 34 of the handset to the input transformer, over a lead 110. Signals from the transmitter are thus conveyed to input transformer 112 from which the volume control potentiometer 113 conveys the signal to the amplifier 90 and thence through coupling transformer 114 to a conventional push-pull output stage 92, 94 feeding output transformer 116. The secondary winding of the latter transformer has one side grounded,'and the other connected to the normally open contact of contact set c of relay 88. The output circuit is therefore open until push-totalk button 38 is closed, whereupon relay 88 operates and connects the signal lead from the transformer to the speaker 14 at contact set 0, and of course grounds the other speaker terminal at contact set d to complete the talking'circuit.

Tone signal oscillator In the third position of switch 42, deck A completes the circuit supplying power transformer 54, deck B again supplies heater power to the listen amplifier, deck C continues to open the flasher supply circuit, and deck-D reconnects the first stage circuit of the talk amplifier to act as a tone oscillator having a predetermined audible frequency tone output. This is accomplished by incorporating a feed-back circuit from the plate circuit of tube 90 to its input circuit via resistor 120, condenser 118, the wiper deck D and the primary winding of transformer 112. The tube 90 and its associated circuits now form an oscillator, preferably emitting a relatively lowpitched audio signal which, when amplifier and conveyed to speaker 14 (as'in the talk condition), will provide the equivalent of a horn or whistle signal for the vessel. Since the output is connected to speaker only when relay 1 88 is operated, the button 38 is used to turn the signal on and ofi.

' Range signal operation For the last operational condition, switch decks A and B make the same connections as before. Deck C, however, connects a high DC. voltage from lead 86 via lead 122 and the switch Wiper to a relaxation oscillator circuit comprising the flasher lamp St), a similar lamp 124 cmployed as a voltage regulator, the condenser 126, and

a pair of resistors 128 and 130. This circuit also includes in series the normally open contacts of a relay 131 whose coil is energized whenever the push-to-talk button 38 is depressed. The relay is of the slow-release type, so that, when energizedby a momentary closure of' switch 38, its contacts will close and remain closed for a period of the order of ten or fifteen seconds, and will then open again. While the relay 131 operates every time button 38 is depressed, the circuit for energizing the flasher lamp 50 will be completed only when the selector 7 switch is in the range signal selecting condition.

The resistor 130 is adjustable to regulate the frequency of the flasher, being provided with a screw-driver or like adjustment for this purpose. Since the operation of this kind of relaxation oscillation is well known, a detailed description of the cycle of charge and dischargeof the a condenser, and illumination of lamp 59 thereby, is believed to be unnecessary. For the purpose of timing echoes, the frequency of the oscillator is preferably so set that the lamp 50 flashes 11 times each six seconds. The velocity of sound being taken at 1100 feet per second, the flash frequency will result in one flash for each hundred yards of travel time (one way) between the vesseland a reflecting object.

When the operator depresses button 38 momentarily,

, horn 14 will produce a short blast, and the contacts of Y relay 131 will close to start the flasher circuit. By noting the number of flashes which occur beforereceipt of an echo, the operator can readily estimate the distance to the reflecting object; that is, each flash correspond to 100 yards of such distance. The release time-of relay 131 is selected so that the flashing will stop after a reasonable length of time which is longer than any expected 7 echo time. A release time of ten second, for example, will permit the timing of echoes up to 1000 yards, and the operator will be advised as to when a new measurement may be made, because the flasher will stop operating when relay 131 releases and until button 38 is operated to repeat the measuring process. a I

The relatively low signal tone produced by the oscillator-amplifier tube stage is not too well suited for sound ranging purposes. It is lowand may be confused with other signals. A higher pitch tone would be preferable. 7

Therefore, as shown, an auxiliary condenser 132 is connected in series with the oscillator condenser 118 by switch deck D when set in its range position, this serving to raise the pitch of the signal tone to a penetrating high value.

It will be seen from the above descn'ption that all 5r the objects of the invention are satisfied by the-disclosed apparatus in a compact and efiicient manner. Necessary t interconnections of a minimum number of components are made quickly and automatically under control of a single selector switch, and conversion from talk to listen and signal functions is accomplished readily by the operator using button 38 in a natural and simple way. Obviously, however, the invention could be carried out by modified apparatus, and such modifications as falltwithin the spirit of the invention are intended to beincluded within the scope of the appended claims. c

What is claimed is: a i

1. Audible signalling apparatus for marine craftand: the like, comprising a transducer constituting a combined loudspeaker and microphone, a telephone having a transmitter and a receiver, a first amplifier for amplifying the output of said telephone transmitter, a second amplifier for amplifying the output of said transducer when used as a microphone, a relay operable to connect said transducer selectively to the input of said second amplifier and to the output of said first amplifier, a switch at said telephone for operating said relay, a selector switch to disable said second amplifier, means including a feedback circuit controlled by said selector switch whereby said first amplifier may be operated selectivelyas a signal oscillator, means for connecting said. telephone receiver to the output of said second amplifier, and'means for con necting said telephone transmitter to the input of said first amplifier. Y i

2. Audible signalling apparatus as set forth in claim 1,. including means controlled by said selector switch for modifying said feedback circuit to alter the frequency of oscillation to a different value. I

References Cited in the file of this patent UNITED STATES PATENTS I V Torre June 10," 1884 

